Pulverized fuel combustion apparatus



June 13, 1933. w. A. WHITE PULVERIZED FUEL COMBUSTION APPARATUS Filed Sept. 8, 1931 Patented June 13,

wmmaiu lALBEB'l? winner nmin mm s, imagine, lemm To} I MARINE ENGINEERING comrniw, QLI ITE on rmnB RN-on-TYN sustain) This invention relates to pulverized fuel] enames rum. ebminjs ajs mames Application nledseptember 8, 1931, Ser1al fl'o. 156L774; and in Great Britain September 11, 133(Lj h Combustion apparatusand more specifically to furnace fronts and burners therefor and means for regulating the amountandwtem peratureof the combustion airl- V I The invention is applicable though not restricted to the combustion of pulverized fuel such ascoal, the m in object being toprovide asimple and improved construction adapted to ensure complete combustion; another ob *ject is to provide improved means for heat ing and for regulating theamountand temperature of combustion air.

With these objects in view the invention consists in the features hereinafter described and claimed in the appended claims. I h Referring to the accompanying diagram- Inatic drawings pulverizedifueliin Idancewith the inf y vention; i v i a u v t and plan respectively of-a form of-rotary Figure -1 shows ma ma-i arrangement of a steam generating plant operating wlth j Figure 2 shows aneleyation of the furnace front? y I 3 Figures 3 and 4 show sectional elevation regulator, while fina Figures 5 and fi showsimilar views of a formofslidingregulator. 1 In{carryingthe invention intoefi ejct ac? cording to theformillustrated in Figure 1 as applied to a steam'generator,'32, having a furnace flue, 33, combustion chamber, 34, re

turn tubes, 35,andwsmoke-box, 36, air is forced by a fan,37, through a preheater 38, ofany usualor suitable construction 841E;

drawing the mixture ofpulverizedfuel and c rangedinfthe uptake, a-part1uof the air so i heated passing into the furnace front, 39;to

i by help ofa burner, 10, of any suitable type.

providesecondary combustion air for the pulverized fuel, e. coal, which is burned This burner ispreferably of the type comprising a tangential inlet, 11,-for the pulverized fuel and primary air, (see also Figure 2) leading to an annulus,"12, of pear-shaped cross-section, the mixture of pulverized fuel issuing from its small end being sandwiched between inner and outer supplies of secondary air, which can be regulated as desired.

From the duct, 13, leading preheated air to the furnace front 39,;a branch, l l, passes to to the pulverizer, 1 5, this branch: being provided with acontrollable inlet,- 1 6, for cold Any suitable regulating: device used for this purpose, a convenient formgber ing shown 1n =F1gures 3 an'dMlu This device movement into correspondenceto any desired extentwvith theapertures, 18. v; t i

In some cases,a connecting pipe, 1.3a,;preferably controllable,may pass from the smoke:

box,36,to the pipe, 14, the objectof thisconnection being to lead high-temperature gases from the smoke-boxiintc theainstream to the pulverizer in orderQfor example, to assist indrying excessively wet fuelaw d 1U '11 a At the mouth of the? furnace flue, 33, a

length of tube, \20, ora boxf like structure of equivalent functions, curved tokfit within it over any desired arc of the: circumference is exposed to theradiant heatiof the furnace: so

as to constitute a high-temperatureheater, air

primary combustion air therefrom and dis charging it, through itheipi pe, 2-5, to. the burneritself, while Tfinally a by-pass,i26,, is provided leading to thehfaninlet from the branch, pipe, 14;, and short-circuitingthe puls verizer, 15,1this by.-pass 1being1a1so :controllable for example, by t-heshutter regula tor shown in Figuresfifandwfi, in whicha 9 slide, 27, is provided, having-a circular aper-z ture, 28, which canbepbrought into any de sired positiongin relation to the boreof the by-pass.

The adjustable byj-pas'sf' 26, an

(a) a control for the air heated in tube, 20, g by the radiant heat of the furnace; (b) a c'ontrollable supply of cold air to inlet, 16'; (0') a controllable by-pass, 26, from the pulverizer inlet to the fan inlet,"and a controllable supply ofhightemperature gases from smoke-box to pipe, 14.

' The formof the invention described above includes all the controls specified, but depending on the requirements of :a particular design, the installation may be simplified, if desired, by the omission of one or more of 'It'Will be seen in addition that the nature of the component parts of the installation, e. g, the high-temperature heater, may take many'differentforms Without exceedlng the scope of the invention. a I

Having now described my invention,,What I claim as new and desireto secure by Let-, ters Patent is 1. A pulverized fuel installation for steam generators comprising a steam generator having a combustion space, a burner positloned at the mouth of said space, a furnace front surrounding said burner, a preheater positioned to be impinged upon by the flue gases, a trunk connecting the preheaterand the furnace front, a pulverizer having an intake and an outlet, a fan having an inlet and an out let, a trunk connecting the outlet of the pulverizer to theinlet of; the fan, an air .trunk connecting the furnace front With the intake of the pulverizer,-and a trunk connecting the outlet of said fan to the burner.

2. A pulverized fuel installation for steam generators comprising a steam generator hav: ing a combustion space, a burner positioned at the mouth of said space, a furnace front surrounding said burner, a preheater positioned to be impinged upon by thefiue gases, a trunk connecting the preheater and the fur+ nace front, a ulverizer havingan intake and an outlet, a an having an inlet and an outlet, a trunk connecting the outlet of the pulverizer to the inlet of the fan, an air trunk connecting the furnace frontwiththe intake of the pulverizer, and a trunk connecting the outlet of said fan to the burner, an air heating tube positioned in the mouthof thecombustion space, means for controlling the flow of air from theifurnace front through said tube and means for delivering the air from the air heating tube to the air trunk connecting the furnace front with the intake of the pulverizer.

3. A pulverized fuel installation for steam 'trunkconnec ting the furnacefront withthe intake of the pulverizer, a trunk connecting the outlet of said fan'to the burner, a pipe adapted to lead, the furnace gases to the air trunk connecting the furnace fron t w ith the intake-of the .pulverizer and means for controllingthe volume of said gases.

' 4. A pulverized fuel installationfor steam generators comprising a steam generator hav ing a combustion space, a burnerpositioned at themouth jof ,SillCl: space, a furnace front surrounding said burner, a preheater positioned tobe impinged upon by the flue gases, a. trunk connecting the preheater and thefurnace front, a pulverizer having an intakeand an outlet, av fan having an inletand an outlet, a trunk connecting the outlet of the pulverizer to the inlet of the, .f'an,,an air trunk con-. necting the furnace front With theintake of the pulverizcr, a trunk connecting theoutlet of said to the burner, a tube connecting the intake of the pulverizer withv the outlet thereof, and means for controlling the air bypassed through said tube. r I '5, A pulverized fueliinstallation forsteam generators comprising a steam generator having a combustion space, a burner positioned at the mouth of saidzspace, a furnace front surrounding said burner, a preheater positioned to be impinged upon by the flue gases,

a trunk connecting the preheater. and the furnace front, a pulverizer, having an intake and an outlet, afan having aninletand an outlet, a trunk connecting the outletof the pulverizer to the inletof the fan, an air trunk connecting the furnace front with theintake of the, pulverizer, atrunk connecting; the outlet of said fan totheburner, an extra air in? let for the admission of ,cold'air positioned in the air trunk connectingthe,furnacefront with. the intake of the pulverizer and adj acent said intake, and means forv controlling 1 the flow of air. through said extra air inlet. r r

In testimony whereof I, have name liO'lJlllS specification,

signed my 

